An optical fiber sensor system for fire detection in hazardous environments

Optical fiber sensors can overcome many of the shortcomings of conventional electronic sensors. This work describes an optical-fiber fire-detection system comprising temperature and smoke sensors interrogated by a time division multiplexing technique. The proposed fire-detection system not only monitors temperature variations in numerous points, but also provides an approximate evaluation of the density of any smoke present. The system is configured as a network that can be easily expanded, as shown by the results of experimental testing on a system composed of four temperature sensors and one smoke sensor.